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contracts...Guess.sol

// SPDX-License-Identifier: GPL-3.0

pragma solidity 0.8.18;

/**
 * Guess a word with a clue.
 */
contract Guess {
    address owner;
    string mysteryText;
    string clue;
    // Mapping of people who have already try a guess.
    mapping(address => bool) voters;
    address winner;

    constructor() {
        owner = msg.sender;
    }

    modifier onlyOwner() {
        require(msg.sender == owner, "You are not the owner of the contract.");
        _;
    }

    modifier canGuess() {
        require(voters[msg.sender] == false, "You have already try a guess.");
        _;
    }

    modifier readyToPlay() {
        require(
            keccak256(abi.encodePacked(mysteryText)) !=
                keccak256(abi.encodePacked("")),
            "Mystery text is not set yet."
        );
        _;
    }

    modifier emptyGame() {
        require(
            keccak256(abi.encodePacked(mysteryText)) ==
                keccak256(abi.encodePacked("")),
            "Mystery text already set."
        );
        _;
    }

    function setWordAndClue(string memory _text, string memory _clue)
        public
        onlyOwner
        emptyGame
    {
        if (
            keccak256(abi.encodePacked(_text)) ==
            keccak256(abi.encodePacked("")) ||
            keccak256(abi.encodePacked(_clue)) ==
            keccak256(abi.encodePacked(""))
        ) {
            revert("The guess or clue are not compliant");
        } else {
            mysteryText = _text;
            clue = _clue;
        }
    }

    function makeAGuess(string memory _guess)
        public
        readyToPlay
        canGuess
        returns (bool)
    {
        voters[msg.sender] = true;
        bool isFound = keccak256(abi.encodePacked(_guess)) ==
            keccak256(abi.encodePacked(mysteryText));

        if (isFound) winner = msg.sender;

        return isFound;
    }

    function getClue() public view readyToPlay returns (string memory) {
        return clue;
    }

    function getWinner() public view returns (bool, address) {
        if (winner == address(0)) return (false, winner);
        else return (true, winner);
    }
}